Riot Fear: Could U.K.-Style Destruction Happen Here?

With riots breaking out across the U.K., some are wondering if the unrest could spread to America. Already in the past few months, youth mobs have wreaked havoc in Philadelphia, Milwaukee and Cleveland.

The rioting in Britain, now entering a sixth day, has prompted authorities to add 16,000 police in the streets of London. Mob rule has taken place across the capital and quickly spread to smaller British cities, including Manchester, Birmingham and Liverpool. On Wednesday three men were killed when they were hit by a car while reportedly defending their neighborhood from looters.

Now that youth mobs in Philadelphia have led to new government action, questions remain: why is this happening, and what is the likelihood of such activity amongst American youth?

The city of Philadelphia has now begun a coordinated response to flash mobs and teen violence that has recently plagued the city and terrorized residential areas.

A Philadelphia man was assaulted by a group of about 30 who were believed to have gotten together through Twitter, according to the Associated Press. On June 23 a few dozen young people looted several hundred dollars worth of merchandise in the Philadelphia suburb of Upper Darby, Pa.

On Monday, Philly Mayor Michael A. Nutter reduced the citywide curfew to 9 p.m. on Fridays and Saturdays for all minors under the age of 18 in targeted enforcement districts.

"This nonsense must stop," Nutter said on Sunday at Mount Carmel Baptist Church in West Philadelphia. "If you wanna act like a butthead, your butt's gonna get locked up. If you wanna act like an idiot, move; we don't want you here anymore."

And Philadelphia is not alone: this weekend, Milwaukee shuddered as a mob stormed the fairgrounds at the Wisconsin state fair. And on July 4 in the Cleveland suburb of Shaker Heights, a group of 1,000 youths organized through social networking sites to fight and disrupt an event.

"The age range is interesting -- of most of these riots, it tends to be in the teenage to early 20s by in large," Frank Farley, a psychologist at Temple University, told ABC News. "That's a big age for thrill seeking and risk-taking."

Adding to the contagion for the young people participating in such wanton destruction are the bleak economic outlook, seemingly unending high unemployment and a deep distrust of government.

"It feels like the whole world is going to implode … so with some of these youth, they're unemployed and angry, they feel the government isn't doing anything about it," Farley said.

ABC News consultant Brad Garret, who was an FBI agent in Washington, D.C. for 30 years, says that he's not sure if he's seen a combination of conditions like today's facing the youth of America.

"When you get people on the edge anyway, and you pull one brick out of their wall, it can collapse," he said.

There are signs of hope for the U.S. though. The chaos seen in Britain is less likely to occur here, because American cities are generally less segregated than Britain's. In addition, police forces in America have gotten much better at fighting and preventing crime and anti-social behavior.